I've never seen Luce live, but that version was different enough from the version usually played on the radio (possibly owing to technical limitations requiring an acoustic guitar, less FX, whatever). Not being a (serious) musician myself, I can only guess at some of the things that keep performing the same old songs fresh would be bits and piece of improvisation that you may throw in, and whatever "vibe" you may get back from the audience.
My only consistent point of reference would be Peter's favorite band, Barenaked Ladies, who I've seen countless times, and who have undoubtably played their hit "If I had $1,000,000 Dollars" what must seem like to them over a million times.
Nonetheless, with those opening chords, the crowd goes mad, which must help with the tedium. Also, BNL is well-known for their improvisational and comedic abilities. Luce, less so, but still, getting paid to play music probably beats the hours I sit in front of my computer pretending to work. (Although it's a more stable gig, and here I am posting to the 10@10 boards. :-)